Histometric evaluation of periodontal surgery. I. The modified Widman flap procedure.

The present investigation was performed in the Rhesus monkey to determine the effect of the modified Widman flap procedure on the level of the connective tissue attachment and supporting alveolar bone. Two adult male Rhesus monkeys were used. Eighteen contralateral pairs of periodontal pockets were produced in a standardized manner. Surgical treatment of the pockets was performed around experimental teeth and the contralateral teeth were used as the unoperated controls. Twelve months following treatment the animals were sacrificed and histological sections obtained. Using the cemento-enamel junction (CEJ) as a fixed reference point, linear measurements along the root surface were made to the most apical cells of the junctional epithelium (JE), to the crest of the interproximal alveolar bone (CR), and to the apical extent of angular bony defects (AAD). These measurements from operated and unoperated pockets were then compared. The data revealed that treatment of periodontal pockets using the modified Widman flap procedure produced no gain in connective tissue attachment and no increase in crestal bone height. In angular bony defects a certain degree "bone fill" was noted. This bone repair was never accompanied by new connective tissue attachment.